Don't forget that we can always post a full crop of a photo for IQ discussion. A full crop shows a small portion of the full size image with the pixels at 100% size. In other words, if I take a full size 18MP photo with my 60D which is 5184 x 3456 pixels, that would be too big to post here. But if I want to discuss certain aspects of that photo I can crop out the important part and post it. For example I could crop out a part of the photo that is only 800 x 800 pixels but showed the pixels full size. For pixel peaking that would work. Full crops to discuss IQ or a good option in many cases.

I do agree that scaling the entire image down to a smaller size is not the best way to examine it for IQ.
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